Equity and Redeemable Preferred Stock (Details Textual) (USD $)	12 Months Ended
	Dec. 31, 2012 Vote	Dec. 31, 2011	May 27, 2010
Equity and Redeemable Preferred Stock (Textual) [Abstract]
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	190,000,000	190,000,000
Common stock, shares issued	18,426,831	18,416,957	17,489,693
Common stock, shares outstanding	17,275,852	18,323,443
Common stock, Number of vote per share	1
Number of warrants issued	2,419,753
Warrants issued to purchase common stock, shares	2,419,753		2,419,753
Common stock, warrants exercise price per share	27.33
Preferred stock, shares authorized	10,000,000	10,000,000
Preferred stock, par value	$ 0.001	$ 0.001
Cumulative participating convertible preferred stock, dividend rate percentage	7.00%	7.00%
Preferred stock, shares issued	964,247	1,007,444
Preferred stock, shares outstanding	958,333	1,003,108
Cumulative Participating Convertible Preferred Stock [Member]
Equity and Redeemable Preferred Stock (Textual) [Abstract]
7% Preferred Stock Share Authorized	2,000,000
Conversion price per share	$ 23.30574
Basis of conversion	(i) the closing sale price of the common stock exceeded 155% of the conversion price for a specified period and (ii) the common stock has been listed on the New York Stock Exchange or NASDAQ. The Company may also cause the conversion of all shares of 7% preferred stock immediately prior to the consummation of an underwritten initial public offering of the common stock if (i) the holders of two-thirds of the then outstanding shares of 7% preferred stock approve the conversion and (ii) the common stock has been listed on the NYSE or NASDAQ.
Maximum percentage of sale price of common stock for conversion	155.00%
Outstanding shares approve for conversion	66.67%